1. Technical Field
This invention relates to adhesive compositions comprising a phosphorylated compound. In another aspect, this invention relates to adhesive compositions comprising a carboxylic acid functional polymer. This invention also relates to methods of adhering a restorative material to a substrate, and in another aspect to methods of adhering a dental restorative such as amalgam to hard tissue such as dentin or enamel.
2. Description of the Related Art
Dental amalgams and restorative composites are used extensively for intracoronal and extracoronal restorations. Amalgam, however, does not adhere to tooth structure and the dentist must prepare the tooth cavity with dovetails and various cutout grooves that mechanically lock the amalgam into the cavity. Such preparation, however, results in excavation of more tooth structure than would otherwise be necessary if there was good adhesion between the tooth structure and the amalgam. Moreover, leakage at the interface of the amalgam and cavity wall (known as "microleakage") tends to occur. This microleakage allows penetration of bacteria, soluble salts, and saliva into any space between the amalgam and tooth structure. This can lead to inflammation, pulp irritation, demineralization of the tooth, corrosion of the amalgam, and other attendant complications. An adhesive seal between amalgam and tooth structure could minimize and/or prevent microleakage and allow for a stronger restoration due to excavation of less tooth material.
Products claiming to make amalgam adhesive to tooth structure are available. One such product is sold in a kit under the trademark AMALGAMBOND.TM. (Parkell Co.). This product is a liquid adhesive to be coated directly onto tooth structure. The active ingredients in the adhesive include 4-META (4-methacryloxyethyl trimellitic anhydride) and TBB (tri-n butyl borane). Other products which similarly involve coating a specific curable resin directly onto tooth structure to make amalgam adhere are available under the trademarks PANAVIA.TM. Dental Adhesive (Kuraray Company) and SUPERBOND.TM. Adhesive (Sun Medical Co., Ltd., Kyoto, Japan). These latter products also are difficult to employ, since there are a number of required preparatory steps for their application and curing.
Adhesive compositions that employ phosphoruscontaining free-radically polymerizable compounds have been reported in the literature, see, e.g., M. Buonocore, W. Wileman, and F. Brudevold, J. Dent. Res., 35, 846 (1956), M. Buonocore and M. Quigley, J. Amer. Dent. Assoc., 57, 807 (1958), M. Anbar and E. Farley, J. Dent. Res., 53, 879 (1974), E. Farley, R. Jones, and M. Anbar, J. Dent. Res., 56 1943 (1977), U.S. Pat Nos. 3,882,600, 3,997,504, 4,222,780, 4,235,633, 4,259,075, 4,259,117, 4,368,043, 4,383,052, 4,499,251, 4,514,342, 4,515,930, 4,537,940, 4,539,382, and 4,544,467, European published patent application No. 0 058 483, and Japanese laid-open patent application (Kokai) Nos. 57-143372 and 57-167364.
U.S. Pat. No. 3,513,123 (Saffir) describes a curable epoxy composition that can be added to amalgam in order to make the amalgam adhere to tooth structure. The curable epoxy composition contains a glycidyl ether type resin and a polyamine hardening agent.
U.S. Pat. No. 4,064,629 (Stoner) describes a method for applying amalgam restorations. The method involves precoating the surfaces of a cavity within a carious tooth with a layer of an "adhesive-metal" lining composition. The metal of the lining composition is amalgamated by diffusion of the mercury from the subsequently applied conventional dental amalgam filling. The "adhesive-metal" lining composition is said to improve corrosion resistance of the dental amalgam filling and also to promote bonding between the amalgam restoration and the cavity surfaces.
U.S. Pat. No. 4,001,483 (Lee, Jr. et al.) describes dental compositions for sealing margins between tooth structures and amalgam restorations therein, the compositions containing (a) an alkylene glycol dimethacrylate and/or its oligomer, (b) a polymerization initiator, (c) a polymerization accelerator and (d) a secondary monomer additive.
U.S. Pat. No. 3,574,943 (Stark) describes a method of restoring a carious tooth whereby the cavity is excavated, lined with a layer of a polysiloxane pressure sensitive adhesive polymer dissolved in a fluorocarbon, and filled with amalgam. The polysiloxane layer is said to act as a barrier to leakage.
Further articles that describe bonding of amalgam to tooth structure by precoating the tooth with adhesive resin include M. Staninec and M. Holt, Journal of Prosthetic Dentistry (1988), Vol. 59, pp. 397-402, A. Lacey and M. Staninec, Quintessence International (1989), Vol. 20, pp. 521-524, Y. Aboush and C. Jenkins, Br. Dent. J. (1989), Vol. 166, pp. 255-257, Y. Aboush and R. Elderton, Br. Dent. J. (1991), Vol. 170, pp. 219-222, and Y. Aboush and R. Elderton, Dent. Mater. (1991), Vol. 7, pp. 130-132. The last article involves adhesion to previously hardened amalgam, whereas the other articles involve adhesion to fresh amalgam. Also, A. Ben-Amar, J. Am. Dent. Assoc. (1989) Vol. 119, pp. 725-728, describes a reduction in microleakage at the margins of amalgam restorations when "SCOTCHBOND" Dual Cure Dental Adhesive resin (3M) is applied to cavity margins prior to application of amalgam, and M. Mitrosky, Jr., Quintessence International (1981) Vol. 9, pp. 871-874, describes the use of ethyl cyanoacrylate as a bonding agent beneath amalgam and composite restoratives. H. J. Staehle et al., Dtsch. Zahnartzt (1988) Vol. 43, pp. 952-957, describes the use of various dental adhesives and varnishes to adhere amalgam to dentin.
Japanese Kokai 63-175085 describes an adhesive composition comprising an acid functional monomer, polymer, or copolymer, a vinyl monomer in which the acid functional component is soluble, an organic peroxide, and an aromatic amine or sulfinate salt. The composition is said to bond living tooth tissue to composites and amalgams.
French Patent 2,561,521 describes an intermediate adhesive composition for sealing dental cavities and chemically securing amalgams, comprising a metal powder dispersed in an adhesive varnish. The composition contains metal powder, cellulosic varnish, ethyl acetate, amyl propionate, fluoride, and oil of pimento leaf.
Japanese Kokai 63-250310 describes dental adhesive compositions containing (a) cellulose ether, (b) a vinyl monomer, (c) an organic peroxide, and (d) an aromatic amine or a sulfinate. The composition is said to be applicable to a wide variety of restorative materials, including composite resins, amalgam, alumina, gold, alloys, polymethyl methacrylate, polycarbonate, and the like.